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Rigorous three-dimensional relativistic equation for quark-antiquark bound states at finite temperature derived from the thermal QCD formulated in the coherent-state representation
A rigorous three-dimensional relativistic equation for quark-antiquark bound
states at finite temperature is derived from the thermal QCD generating
functional which is formulated in the coherent-state representation. The
generating functional is derived newly and given a correct path-integral
expression. The perturbative expansion of the generating functional is
specifically given by means of the stationary-phase method. Especially, the
interaction kernel in the three-dimensional equation is derived by virtue of
the equations of motion satisfied by some quark-antiquark Green functions and
given in a closed form which is expressed in terms of only a few types of Green
functions. This kernel is much suitable to use for exploring the deconfinement
of quarks. To demonstrate the applicability of the equation derived, the
one-gluon exchange kernel is derived and described in detail
Massive Gauge Field Theory Without Higgs Mechanism I. .Quantization
According to the conventional concept of the gauge field theory, the local
gauge invariance excludes the possibility of giving a mass to the gauge boson
without resorting to the Higgs mechanism because the Lagrangian constructed by
adding a mass term to the Yang-Mills Lagrangian is not only
gauge-non-invariant, but also unrenormalizable. On the contrary, we argue that
the principle of gauge invariance actually allows a mass term to enter the
Lagrangian if the Lorentz constraint condition is taken into account at the
same time. The Lorentz condition, which implies vanishing of the unphysical
longitudinal field, defines a gauge-invariant physical space for the massive
gauge field. The quantum massive gauge field theory without Higgs mechanism may
well be established by using a BRST-invariant action which is constructed by
the Lagrange undetermined multiplier procedure of incorporating the Lorentz
condition and another condition constraining the gauge group into the original
massive Yang-Mills action. The quantum theory established in this way shows
good renormalizability.Comment: 34 pages, latex, 3 figure
059<p type="texpara" tag="Body Text" et="f_0" bin="clone" >Massive Gauge Field Theory Without Higgs Mechanism Massive Gauge Field Theory Without Higgs Mechanism III. Proof of Renormalizability
~It is shown that the quantum massive non-Abelian field theory established in
the former papers is renormalizable. This conclusion is achieved with the aid
of the Ward-Takahashi identities satisfied by the generating functionals which
were derived in the preceding paper based on the BRST-symmetry of the theory.
By the use of the Ward-Takahashi identity, it is proved that the divergences
occurring in the perturbative calculations for the massive gauge field theory
can be eliminated by introducing a finite number of counterterms in the
effective action. As a result of the proof, it is found that the
renormalization constants for the massive gauge field theory comply with the
same Slavnov-Taylor identity as that for the massless gauge field theory. The
latter identity is re-derived from the Ward-Takahashi identities satisfied by
the gluon proper vertices and their renormalization.Comment: 25 pages, latex, no figure
Lorentz-Covariant Quantization of Massive Non-Abelian Gauge Fields in The Hamiltonian Path-Integral Formalism
The massive non-Abelian gauge fields are quantized Lorentz-covariantly in the
Hamiltonian path-integral formalism. In the quantization, the Lorentz
condition, as a necessary constraint, is introduced initially and incorporated
into the massive Yang-Mills Lagrangian by the Lagrange multiplier method so as
to make each temporal component of a vector potential to have a canonically
conjugate counterpart. The result of this quantization is confirmed by the
quantization performed in the Lagrangian path-integral formalism by applying
the Lagrange multiplier method which is shown to be equivalent to the
Faddeev-Popov approach
Massive Gauge Field Theory Without Higgs Mechanism II. Ward-Takahashi Identities and Proof of Unitarity
In our previously published papers, it was argued that a massive non-Abelian
gauge field theory in which all gauge fields have the same mass can well be set
up on the gauge-invariance principle. The quantization of the fields was
performed by different methods. In this paper, It is proved that the quantum
theory is invariant with respect to a kind of BRST-transformations. From the
BRST-invariance of the theory, the Ward-Takahashi identities satisfied by the
generating functionals of full Green's functions, connected Green's functions
and proper vertex functions are successively derived. As an application of the
above Ward-Takahashi identity, the Ward-Takahashi identity obeyed by the
massive gauge boson propagator is derived and the renormalization of the
propagator is discussed. Furthermore, based on the Ward-Takahashi identity, it
is exactly proved that the S-matrix elements given by the quantum theory are
gauge-independent and hence unitary.Comment: 18 pages, latex, no figure
Quantization of The Electroweak Theory in The Hamiltonian Path-Integral Formalism
The quantization of the SU(2)U(1) gauge-symmetric electroweak theory
is performed in the Hamiltonian path-integral formalism. In this quantization,
we start from the Lagrangian given in the unitary gauge in which the unphysical
Goldstone fields are absent, but the unphysical longitudinal components of the
gauge fields still exist. In order to eliminate the longitudinal components, it
is necessary to introduce the Lorentz gauge conditions as constraints. These
constraints may be incorporated into the Lagrangian by the Lagrange
undetermined multiplier method. In this way, it is found that every component
of a four-dimensional vector potential has a conjugate counterpart. Thus, a
Lorentz-covariant quantization in the Hamiltonian path-integral formalism can
be well accomplished and leads to a result which is the same as given by the
Faddeev-Popov approach of quantization.Comment: 9 pages, no figure
Lorentz-Covariant Quantization of Massless Non-Abelian Gauge Fields in The Hamiltonian Path-Integral Formalism
The Lorentz-covariant quantization performed in the Hamiltonian path-integral
formalism for massless non-Abelian gauge fields has been achieved. In this
quantization, the Lorentz condition, as a constraint, must be introduced
initially and incorporated into the Yang-Mills Lagrangian by the Lagrange
undetermined multiplier method. In this way, it is found that all Lorentz
components of a vector potential have thier corresponding conjugate canonical
variables. This fact allows us to define Lorentz-invariant poisson brackets and
carry out the quantization in a Lorent-covariant manner. Key words: Non-Abelian
gauge field, quantization, Hamiltonian path-integral formalism, Lorentz
covariance.Comment: 11 pages no figure
Massive Gauge Field Theory Without Higgs Mechanism IV. Illustration of Unitarsity
To illustrate the unitarity of the massive gauge field theory described in
the foregoing papers, we calculate the scattering amplitudes up to the fourth
order of perturbation by the optical theorem and the Landau-Cutkosky rule. In
the calculations, it is shown that for a given process, if all the diagrams are
taken into account, the contributions arising from the unphysical intermediate
states included in the longitudinal part of the gauge boson propagator and in
the ghost particle propagator are completely cancelled out with each other in
the S-matrix elements. Therefore, the unitarity of the S-matrix is perfectly
ensured.Comment: 30 pages, latex, 9 figure
Some Extensions of Probabilistic Logic
In [12], Nilsson proposed the probabilistic logic in which the truth values
of logical propositions are probability values between 0 and 1. It is
applicable to any logical system for which the consistency of a finite set of
propositions can be established. The probabilistic inference scheme reduces to
the ordinary logical inference when the probabilities of all propositions are
either 0 or 1. This logic has the same limitations of other probabilistic
reasoning systems of the Bayesian approach. For common sense reasoning,
consistency is not a very natural assumption. We have some well known examples:
{Dick is a Quaker, Quakers are pacifists, Republicans are not pacifists, Dick
is a Republican}and {Tweety is a bird, birds can fly, Tweety is a penguin}. In
this paper, we shall propose some extensions of the probabilistic logic. In the
second section, we shall consider the space of all interpretations, consistent
or not. In terms of frames of discernment, the basic probability assignment
(bpa) and belief function can be defined. Dempster's combination rule is
applicable. This extension of probabilistic logic is called the evidential
logic in [ 1]. For each proposition s, its belief function is represented by an
interval [Spt(s), Pls(s)]. When all such intervals collapse to single points,
the evidential logic reduces to probabilistic logic (in the generalized version
of not necessarily consistent interpretations). Certainly, we get Nilsson's
probabilistic logic by further restricting to consistent interpretations. In
the third section, we shall give a probabilistic interpretation of
probabilistic logic in terms of multi-dimensional random variables. This
interpretation brings the probabilistic logic into the framework of probability
theory. Let us consider a finite set S = {sl, s2, ..., Sn) of logical
propositions. Each proposition may have true or false values; and may be
considered as a random variable. We have a probability distribution for each
proposition. The e-dimensional random variable (sl,..., Sn) may take values in
the space of all interpretations of 2n binary vectors. We may compute absolute
(marginal), conditional and joint probability distributions. It turns out that
the permissible probabilistic interpretation vector of Nilsson [12] consists of
the joint probabilities of S. Inconsistent interpretations will not appear, by
setting their joint probabilities to be zeros. By summing appropriate joint
probabilities, we get probabilities of individual propositions or subsets of
propositions. Since the Bayes formula and other techniques are valid for
e-dimensional random variables, the probabilistic logic is actually very close
to the Bayesian inference schemes. In the last section, we shall consider a
relaxation scheme for probabilistic logic. In this system, not only new
evidences will update the belief measures of a collection of propositions, but
also constraint satisfaction among these propositions in the relational network
will revise these measures. This mechanism is similar to human reasoning which
is an evaluative process converging to the most satisfactory result. The main
idea arises from the consistent labeling problem in computer vision. This
method is originally applied to scene analysis of line drawings. Later, it is
applied to matching, constraint satisfaction and multi sensor fusion by several
authors [8], [16] (and see references cited there). Recently, this method is
used in knowledge aggregation by Landy and Hummel [9].Comment: Appears in Proceedings of the Second Conference on Uncertainty in
Artificial Intelligence (UAI1986
Massive gauge field theory without Higgs mechanism
It is argued that the massive gauge field theory without the Higgs mechanism
can well be set up on the gauge-invariance principle based on the viewpoint
that a massive gauge field must be viewed as a constrained system and the
Lorentz condition, as a constraint, must be introduced from the beginning and
imposed on the Yang-Mills Lagrangian. The quantum theory for the massive gauge
fieldis may perfectly be established by the quantization performed in the
Hamiltonian or the Lagrangian path-integral formalism by means of the Lagrange
undetermined multiplier method and shows good renormalizability and unitarity
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